Argument: 14th amendment was written at a different time, but still applies
Linda Chavez. "The Case For Birthright Citizenship." Wall Street Journal. August 11th, 2010: "Proponents of repeal argue that the 14th Amendment was passed after the Civil War to guarantee citizenship to freed slaves, and that it was never intended to grant rights to the offspring of illegal aliens. But this argument is a non sequitur. At the time of the adoption of the amendment, there was no category of "illegal alien" because immigration was unrestricted and unregulated. If you secured passage to the United States, or simply walked across the open border with Mexico or Canada, you could stay permanently as a resident alien or apply to be naturalized after a certain number of years. And if you happened to give birth while still an alien, your child was automatically a citizen—a right dating back to English common law."